// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_HEAP_INCREMENTAL_MARKING_INL_H_
#define V8_HEAP_INCREMENTAL_MARKING_INL_H_

#include "src/heap/incremental-marking.h"

#include "src/heap/mark-compact-inl.h"
#include "src/isolate.h"
#include "src/objects-inl.h"
#include "src/objects/maybe-object.h"

namespace v8 {
namespace internal {

    void IncrementalMarking::TransferColor(HeapObject from, HeapObject to)
    {
        if (atomic_marking_state()->IsBlack(to)) {
            DCHECK(black_allocation());
            return;
        }

        DCHECK(atomic_marking_state()->IsWhite(to));
        if (atomic_marking_state()->IsGrey(from)) {
            bool success = atomic_marking_state()->WhiteToGrey(to);
            DCHECK(success);
            USE(success);
        } else if (atomic_marking_state()->IsBlack(from)) {
            bool success = atomic_marking_state()->WhiteToBlack(to);
            DCHECK(success);
            USE(success);
        }
    }

    void IncrementalMarking::RecordWrite(HeapObject obj, ObjectSlot slot,
        Object value)
    {
        DCHECK_IMPLIES(slot.address() != kNullAddress, !HasWeakHeapObjectTag(*slot));
        DCHECK(!HasWeakHeapObjectTag(value));
        if (IsMarking() && value->IsHeapObject()) {
            RecordWriteSlow(obj, HeapObjectSlot(slot), HeapObject::cast(value));
        }
    }

    void IncrementalMarking::RecordMaybeWeakWrite(HeapObject obj,
        MaybeObjectSlot slot,
        MaybeObject value)
    {
        // When writing a weak reference, treat it as strong for the purposes of the
        // marking barrier.
        HeapObject heap_object;
        if (IsMarking() && value->GetHeapObject(&heap_object)) {
            RecordWriteSlow(obj, HeapObjectSlot(slot), heap_object);
        }
    }

    void IncrementalMarking::RestartIfNotMarking()
    {
        if (state_ == COMPLETE) {
            state_ = MARKING;
            if (FLAG_trace_incremental_marking) {
                heap()->isolate()->PrintWithTimestamp(
                    "[IncrementalMarking] Restarting (new grey objects)\n");
            }
        }
    }

} // namespace internal
} // namespace v8

#endif // V8_HEAP_INCREMENTAL_MARKING_INL_H_
